25002500 Posted August 23, 2010 Share Posted August 23, 2010 Anyone see a problem with topping off Rotella 15w40 with Mobil 5w30? Quote Link to comment https://www.bigmacktrucks.com/topic/15422-engine-oil/ Share on other sites More sharing options...
rhasler Posted August 23, 2010 Share Posted August 23, 2010 Anyone see a problem with topping off Rotella 15w40 with Mobil 5w30?Do not mix oils. Manufacturers use different chemical additives in their oils that are not always compatible. You might get away with mixing two oils of the same grade, but I wouldn't mix 15w40 with 5w30. Quote "Mebbe I'm too ugly and stupid to give up!" Link to comment https://www.bigmacktrucks.com/topic/15422-engine-oil/#findComment-62172 Share on other sites More sharing options...
Rob Posted August 23, 2010 Share Posted August 23, 2010 Do not mix oils. Manufacturers use different chemical additives in their oils that are not always compatible. You might get away with mixing two oils of the same grade, but I wouldn't mix 15w40 with 5w30.I've never seen a 5W30 oil rated for diesel engine usage. I would not mix the two but rather find another oil that is rated for this usage.Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment https://www.bigmacktrucks.com/topic/15422-engine-oil/#findComment-62173 Share on other sites More sharing options...
Mike Posted August 23, 2010 Share Posted August 23, 2010 Isn't COMPATIBILITY a wonderful thing? Even small engines can let you down when you change over or mix different oils together. Like these guys have said: Don't Mix or You'll Fix whatever your working on later. mike Quote Link to comment https://www.bigmacktrucks.com/topic/15422-engine-oil/#findComment-62177 Share on other sites More sharing options...
25002500 Posted August 23, 2010 Author Share Posted August 23, 2010 Isn't COMPATIBILITY a wonderful thing? Even small engines can let you down when you change over or mix different oils together. Like these guys have said: Don't Mix or You'll Fix whatever your working on later. mike Thanks to all of you for this good input.The oil was free, but not worth tearing up an engine.Thanks again. Quote Link to comment https://www.bigmacktrucks.com/topic/15422-engine-oil/#findComment-62182 Share on other sites More sharing options...
bobo Posted August 23, 2010 Share Posted August 23, 2010 5w30 is what Cat says to use in late c15/c16 here in Canada, low sulfer fuel. Our shop used to use in newer company trucks, but not any more. why have 2 types oil so now just 15w40 I've never seen a 5W30 oil rated for diesel engine usage. I would not mix the two but rather find another oil that is rated for this usage.Rob Quote Link to comment https://www.bigmacktrucks.com/topic/15422-engine-oil/#findComment-62184 Share on other sites More sharing options...
rhasler Posted August 23, 2010 Share Posted August 23, 2010 5w30 is what Cat says to use in late c15/c16 here in Canada, low sulfer fuel. Our shop used to use in newer company trucks, but not any more. why have 2 types oil so now just 15w40Current production (2010 emissions) Mack and Volvo engines are are factory filled with 10w30, which they say results in a pretty substantial fuel economy increase. Quote "Mebbe I'm too ugly and stupid to give up!" Link to comment https://www.bigmacktrucks.com/topic/15422-engine-oil/#findComment-62185 Share on other sites More sharing options...
HK Trucking Posted August 23, 2010 Share Posted August 23, 2010 Thanks to all of you for this good input.The oil was free, but not worth tearing up an engine.Thanks again.Use it for oiling the bar & chain on your chain saw.. Quote "If You Can't Shift It Smoothly, You Shouldn't Be Driving It" Link to comment https://www.bigmacktrucks.com/topic/15422-engine-oil/#findComment-62209 Share on other sites More sharing options...
cgallamore Posted August 23, 2010 Share Posted August 23, 2010 this is gona be a long post. sorryi bought my truck in feb. 2010. i was told it had a fresh service, didnt trust em, was a mack dealer and it had hastings filters on it. i ran about 10,000 miles, thought id save a buck and change it myself. went to mack for filters, i had 4 gallons of rottella 15-40 so i went to wally world and got enough rottelllo to finish the oil change. i have run this in my other trucks and equipment with no problems. i thought all (same weight) oil came out of the same barrell just different jugs. in the 10,000 miles my truck didn't use a drop of oil.i pulled out for salt lake city, ran to little america,WY. about 1,300 miles. noticed frame was wet under turbo, appeared turbo leaking oil. checked oil next morning 1 gallon low. when i left it looked like the place was on fire, so much smoke from my truck.contacted mackpro for a turbo replace, as soon as i could work my way to ky. i ran about 9,000 miles and put in 8 gallons of oil.mackpro suggested we try putting mack oil in it and see if that would help. when i seen the price of the turbo i was easy to talk into letting it go one more change.so he put mack oil in. i ran it 15,000 miles turbo and frame still damp, but acceptable. had to add three gallons on that service.i was trying to get as much as i could out of the turbo.im on the next change now, have put 7,000 miles so far and has not used a drop of oil, also turbo and frame are dry.this is kida a long winded way to say i will never mix oil, and will do my best to find out what has allways been used............THERE IS NO WAY I WOULD HAVE BELIEVED THIS STORY IF IT DIDN'T HAPPEN TO ME...... Quote http://www.bigmacktrucks.com/uploads/1272400769/gallery_4852_794_314995.jpg Link to comment https://www.bigmacktrucks.com/topic/15422-engine-oil/#findComment-62215 Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.